Custom Services

@evvm/evvm-js allows users to create their own services interacting with the evvm, they must initially follow the evvm service spec; this documentation focuses on building the signature creation tool that users can then use in their own dapps.

Creation of custom services

Creating a custom service using the @evvm/evvm-js involves creating a class for your service that inherits from BaseService abstract class, extending it with your custom actions, they all must return SignedActions:

import { BaseService, SignedAction } from "@evvm/evvm-js";

interface ICustomActionData {
  /* params as desribed in your service smart contract function */
}

export class MyCustomService extends BaseService {
  async myCustomAction(
      /* params required to build the SignedAction */
  ): Promise<SignedAction<ICustomActionData>> {
    const evvmId = await this.getEvvmID();
    const functionName = "myCustomAction";

    const signature = await this.signer.signGenericEvvmMessage(
      evvmId,
      functionName,
      /* inputs string */,
    );

    return new SignedAcion(this, evvmId, functionName, {
      /* params as described in ICustomActionData */
    });
  }
}

So that you can use MyCustomService as follows:

import { MyCustomService } from "./MyCustomService.ts";
import { MyCustomServiceABI } from "./MyCustomServiceABI.ts";
import { execute, IAbi } from "@evvm/evvm-js";

const signer = createSignerWithEthers(ethersSigner);
const myCustomService = new MyCustomService(
  signer,
  "CUSTOM_SERVICE_ADDRESS",
  MyCustomServiceABI as IAbi,
);

const signedAction = await myCustomService.myCustomAction(/* params */);

// an then execute it with:
const txHash = await execute(signer, signedAction);